With the development of modern medicine, researchers have been devoted to reduce pains brought by medical treatments. Use of intravenous retaining needles (also referred to intravenous trocar) can reduce pains caused by repetitive venipuncture to patients and alleviate workload of healthcare workers, which currently has gained wide application. The existing retaining needles generally comprise a puncture needle and a catheter retained in a blood vessel. During use, the catheter is pierced into the blood vessel with the puncture needle; when the catheter completely enters into the blood vessel, the puncture needle is retracted, only retaining the catheter within the blood vessel, prepared for subsequent treatment.
During use, positioning of the retaining needle is very important. After the puncture needle is penetrated into the patient's blood vessel, the blood pressure of the patient will cause a little blood to flow into the hollow puncture needle, such that when the user observes the little blood at a rear part of the puncture needle, it can be determined that the retaining needle is completely positioned and may be retracted. However, the blood-tainted puncture needle will bring many risks to the healthcare workers and other persons who possibly contact medical garbage, such as infection with diseases, etc.
Currently, puncture-proof retaining needles have emerged in markets, but most of them have a complex structure and a high manufacturing cost; therefore, the price is dear, while the operation is inconvenient.
Accordingly, a retaining needle featuring a high safety, a simple structure, cost-effectiveness, and an easy manipulation and a safety mechanism suitable for the retaining needle for guaranteeing its safety are still desirable.